Methods of fixing ink

ABSTRACT

The invention provides methods for providing improved image quality and water resistance of dye based ink images on substrates using aqueous dispersed mordants and dispersed hydrophobic materials.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a divisional of U.S. application Ser. No.09/778,475, filed Feb. 7, 2001, now allowed; which is acontinuation-in-part of U.S. application Ser. No. 09/500,153, filed Feb.8, 2000, now abandoned.

FIELD OF THE INVENTION

[0002] The present invention relates to ink fixing materials and methodsfor fixing dye based inks to solid and porous substrates, for example,walls and fabrics.

BACKGROUND OF THE INVENTION

[0003] Direct inkjet printing onto a variety of substrates such asfilms, papers, and fabrics has been used to generate graphic images.However, for substrates that are either of poor dimensional stability(such as many fabrics), or that are too large to be handled using aconventional inkjet printer (for example, a wall of a room), indirectprinting methods such as transfer printing methods are normallyemployed. Current inkjet transfer printing methods include printing ontofabrics that have adhesive backings adhering them to a release liner, oriron-on transfers.

[0004] Inkjet printing has been used to provide images on a wide varietyof substrates including films, papers, fabrics, and the like.Commercially available inks for ink-jet printers are typically aqueousbased and employ dyes as colorants. Current commercially available inksgenerally lack the simultaneous properties of good image quality (e.g.,high resolution and color density) and waterfastness or washfastnesswhen printed on any of the above-mentioned substrates. This is importantif the image is transferred to a surface that will encounter water or bewashed in normal usage (for example, clothing, room walls, etc.).

[0005] Whether inkjet printing is performed in an industrial process oron a printer attached to a personal computer, there exists a need to beable to print an image on a wide variety of substrates that have thesimultaneous properties of good image quality and waterfastness or evenwashfastness.

SUMMARY OF THE INVENTION

[0006] The present invention provides compositions and processes usefulfor improving image quality and water resistance of dye based inkimages, particularly dye based inks used in inkjet printing. Thecompositions and processes are easy to use and suitable for office andhome use environments.

[0007] In one aspect, the invention provides a method for providing adurable ink image on a substrate. The method comprises the steps ofcoating a surface of the substrate with an aqueous mordant dispersion;printing or transferring a selected image onto the coated surface;optionally drying the image; applying a dispersed hydrophobic materialonto the imaged surface; and drying the dispersed hydrophobic material.The method may optionally further include the step of heating thetransferred and fixed image. The method may also optionally include thestep of drying the coated mordant dispersion before printing ortransferring the image.

[0008] In another aspect, the invention provides another method forproviding a durable ink image on a substrate. The method comprises thesteps of coating a surface of the substrate with an ink fixing mixturecomprising an aqueous dispersion of a mordant and a dispersedhydrophobic material; printing or transferring a selected image onto thecoated substrate; and drying the image and coated ink fixing mixture.The method may further include the step of heating the transferred andfixed image.

[0009] In another aspect, the invention provides a method for providinga durable ink image on a non-porous substrate. The method comprises thesteps of coating a surface of a non-porous substrate with an aqueousfluoropolymer dispersion, printing or transferring an image onto thecoated non-porous substrate; and heating the coated image. The methodmay also optionally include drying the coated fluoropolymer dispersionat ambient temperature prior to printing or transferring the image.

[0010] In still another aspect, image bearing articles are provided thatare prepared by any of the preceding methods.

[0011] In still an another aspect, the invention provides a kit forproviding a durable image on a substrate. The kit comprises an imagetransfer medium, aqueous mordant dispersion, and hydrophobic materialdispersion. The mordant dispersion and hydrophobic material dispersionsmay be supplied separately or as a mixture of the two.

[0012] A feature of the invention is that it provides materials andmeans whereby aqueous inkjet inks may be printed with high resolutionand good color density, and having improved waterfastness andwashfastness compared to prior methods.

[0013] The term “mordant” means a compound which, when present in acomposition, interacts with a dye to prevent diffusion through thecomposition.

[0014] A “non-porous substrate” is a substrate that is not porous toink.

[0015] As used herein, the term “dry” refers to dry to the touch; thatis, does not transfer to a finger when touched.

BRIEF DESCRIPTION OF THE FIGURES

[0016]FIGS. 1-14 are magnified digital images of images prepared usingexamples of the invention and comparative examples.

[0017]FIGS. 15-18 show magnified illustrative views of useful imagetransfer media.

DETAILED DESCRIPTION OF THE INVENTION

[0018] The invention in its various aspects employs two essentialcomponents: a mordant, and a dispersed hydrophobic material. The mordantfunctions to improve wettability of the substrate, and improves imagequality by helping to fix the image. The dispersed hydrophobic materialserves to provide a degree of durability and water resistance andwashfastness to the printed image.

[0019] Suitable mordants are readily dispersible or soluble in water andinclude polymeric dye mordants which may be cationic or neutral,inorganic metal ion containing colloids, and polymer bound metal ioncontaining colloids.

[0020] Polymeric dye mordants include those known in the art for usewith dye based inks, for example, quaternary ammonium groups containingpolymers such as poly(ethyleneiminium) chloride; poly(vinylpyridinium)chloride; poly(N,N-diallyldimethylammonium) bromide;poly(ethyleniminium) chloride; copolymers having quaternary ammoniumgroups such as those disclosed in U.S. Pat. No. 5,712,027 (Ali), U.S.Pat. No. 5,354,813 (Farooq), and U.S. Pat. No. 5,342,688 (Kitchin), allincorporated by reference herein; epichlorohydrin/aminopolymer resins(for example “KYMENE 557H”, commercially available from Hercules, Inc.of Wilmington, Del.); poly(ethylenimine); polyaziridine condensationproducts; homopolymers and copolymers of N-vinylpyrrolidone, forexample, copolymers of N-vinylpyrrolidone and dimethylaminoethylmethacrylate; copolymers of N-vinylpyrrolidone andmethylvinylimidazolium salts; homopolymers and copolymers of acrylamide;homopolymers and copolymers of N,N-dimethylacrylamide; homopolymers andcopolymers of N,N-diallylmethylamine; and condensates ofaminoalkylsilanes, such as 3-aminopropyltriethoxysilane,N,N-diethyl-3-aminopropyltriethoxysilane, etc.

[0021] Non-limiting examples of inorganic metal ion containing colloidsinclude inorganic sols such as alumina colloids, silica colloids,aluminosilicate colloids; and surface treated silica and aluminacolloids that have been surface treated with, for example, alumina, oran organosilane (such as aminopropyltriethoxysilane, etc.).

[0022] Non-limiting examples of polymer bound metal ion containingcolloids include aluminum salts of organic polymers such ashydroxypropyl methylcellulose crosslinked with aluminum ions asdescribed in U.S. Pat. No. 5,686,602, incorporated by reference herein.

[0023] The mordant is applied to the substrate as a 1-50 weight percentsolution, preferably 15-30 weight percent solution in water, and thenoptionally dried prior to imaging.

[0024] Dispersed hydrophobic materials serve to provide an aqueoussource of hydrophobic materials that may be applied to printed images toenhance their waterfastness and washfastness. While dispersed (e.g.,emulsified), the hydrophobic materials are not effective protectiveagents (not hydrophobic), but upon drying, these materials often becomehydrophobic. Thus, it is possible to print directly onto substratestreated with hydrophobic materials using aqueous inks so long as thehydrophobic materials have not yet become hydrophobic. “Hydrophobic” asused herein means that the surface of the material is not readily wettedby water. However, once the emulsions are hydrophobic (for example, byheating after air drying) the printing process is generally difficult tocarry out successfully with aqueous inks. Any hydrophobic material knownin the art that can be dispersed may be used in practice of theinvention. Preferred dispersed hydrophobic materials are fluorinatedorganic compounds, silicones, polyvinyls, polyesters, and polyurethanes.Fluorinated organic compounds are most preferred as hydrophobicmaterials.

[0025] Fluorinated organic compounds useful in practice of the presentinvention include aqueous fluoropolymer dispersions that, when dried,form a surface that is repellent to water. Importantly, fluorinatedsurfactants, by their nature, generally do not provide such repellency.Examples of fluoropolymer dispersions that are useful in practice of theinvention include those sold under the FLUORAD trade designation byMinnesota Mining and Manufacturing Company of St. Paul, Minn., such asFLUORAD FC-359 (an aqueous dispersion of a fluoroalkyl polymer(approximately 20 percent)), FLUORAD FC-461 (an aqueous dispersion of afluoroalkyl copolymer (approximately 27 percent), FLUORAD FC-1355 (anaqueous dispersion of a fluoroalkyl polymer (approximately 15 percent)),FLUORAD FC-405 (a fluoroaliphatic silyl ether approximately 62 percent,ethanol approximately 37 percent, 2-butanone approximately 1 percent)and FLUORAD FC-280 (an aqueous dispersion of a fluoroalkyl polymer(approximately 30 percent)).

[0026] Non-limiting examples of useful silicones include polysiloxanepolymers (such as poly(dimethylsiloxane), poly(methylphenylsiloxane),etc.) and alkoxylated derivatives therefrom such as those described inU.S. Pat. No. 5,932,355, incorporated by reference herein, for thedescription of alkoxylated derivatives of polysiloxane polymers;hydrolyzable or otherwise condensable silanes such as cyclosiloxanes(e.g., octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane,etc.); alkoxysiloxanes (e.g., octyltriethoxysilane,octadecyltriethoxysilane, octyltrimethoxysilane), acyloxysilanes,hydrosilanes, and the like.

[0027] Non-limiting examples of useful polyvinyls includepoly(meth)acrylates (i.e., polymerized ethylenically unsaturatedmonomers) such as hydrocarbyl ester (meth)acrylate polymers (forexample, polymers and copolymers of butyl acrylate, hexyl acrylate,octyl(meth)acrylate, ethyl(meth)acrylate, propyl acrylate, etc.);copolymers of ethylene and vinyl acetate, vinyl chloride, etc.;homopolymers and copolymers of acrylonitrile; homopolymers andcopolymers of styrene.

[0028] When additional washfastness is desired, it is possible toincorporate a co-monomer having a thermosettable group such as methylolacrylamide co-monomer into the polyvinyl copolymers. Many such materialsare available under the RHOPLEX trade designation from Rohm & Haas Co.of Philadelphia, Pa.

[0029] Dispersed hydrophobic materials are typically applied as aqueoussolutions having from 1-50 weight percent solids, or even higher. Whenused alone, the hydrophobic materials are preferably 5-40 weight percentsolids, more preferably 10-30 weight percent solids dispersions. Whencombined with the mordant and applied as a single dispersion, thedispersed hydrophobic materials are preferably present at 5-30 weightpercent solids.

[0030] Method of Making the Invention

[0031] The mordants and dispersed hydrophobic materials may be employedindividually or easily mixed and used as a single dispersion. Whenmixed, reasonable care should be taken to avoid an incompatible mixture,as stability for a period of weeks to years is generally desirable.

[0032] While the solids content of the mordant solution or dispersionand the dispersed hydrophobic materials components is typically in theranges listed above, it may also be important to control the coatingweight (i.e., add on) of the coating applied to the substrate. In someembodiments of the invention, the mordant is applied in an amountsufficient to wet the substrate to allow for rapid ink sorption and thenprinted directly on the damp substrate.

[0033] For typical porous substrates (e.g., fabrics) a wet add on forthe mordant is from about 0.1 part up to about 20 parts wet add on per10 parts fabric by weight, preferably from about 0.5 part up to about 15parts wet add on per 10 parts fabric by weight. For hard non-poroussubstrates typical wet add on for the mordant ranges from about 5 gramsper square meter up to about 500 grams per square meter, preferably fromabout 10 grams per square meter up to about 100 grams per square meter,more preferably from about 30 grams per square meter up to about 70grams per square meter. On the other hand, in some embodiments withparticularly absorbent substrates, it may be advantageous to dry themordant. This is because the substrates would contain excess water whichwould decrease the effectiveness of the mordant.

[0034] Method of Using the Compositions

[0035] The compositions of the invention may be utilized on many typesof fabrics of many different constructions, including for example, wovenfabrics, knit fabrics, and non-woven fabrics. Examples of fabricsinclude, but are not limited to, those having fibers made frompolyamides such as nylon; polyesters such as DACRON; polyolefins such aspolypropylene, polyethylene, etc.; cotton; linen; wool; and rayon.

[0036] In one embodiment, an image is printed or transferred and fixedon fabric. In a first step, the mordant dispersion is first applied tothe cloth covering the area to be imaged, and optionally dried. In asecond step, the image is applied to the treated area, and then theimage is optionally dried. The image may be dried at ambient or roomtemperature (typically, 20° C.-25° C.) or heated at a temperature of upto 100° C. to dry the image. In a third step, a dispersed hydrophobicmaterial is applied to the image bearing surface of the substrate, anddried at ambient or room temperature (typically, 20° C.-25° C.) orheated at a temperature of up to 100° C. to dry the image with optionalheating to a temperature sufficient to remove residual water andoptionally cause chemical crosslinking of the hydrophobic material.Typically, this involves temperatures of up to about 100° C., althoughin some cases, higher temperatures may be useful depending on the natureof the crosslinking chemistry and the substrate. Drying time of thehydrophobic material ranges from about 2 minutes to 24 hours or more,depending upon the drying temperature.

[0037] In another embodiment, the invention provides a method forproviding a durable ink image on a substrate, wherein the methodcomprises the steps of coating a substrate with a mixture of an aqueousmordant and a dispersed hydrophobic material, optionally, drying thecoated substrate, printing or transferring a selected image onto thecoated surface of the substrate, and an optional further step of heatingthe substrate.

[0038] In another embodiment, the invention provides a method forproviding a durable ink image on a non-porous substrate. Examples ofnon-porous substrates include polymeric films, painted surfaces such aswalls, glass, metals, and the like. The method comprises the steps ofcoating a surface of a non-porous substrate with an aqueousfluoropolymer dispersion, printing or transferring an image onto thecoated non-porous substrate, drying, and optionally heating the coatedimage such that the dispersed fluoropolymer material becomeshydrophobic. The method may also optionally include drying the coatedfluoropolymer dispersion at preferably, ambient temperature to 100° C.or more depending on the polymer. Typical drying times range from 2minutes to 24 hours or more depending upon the drying temperature.However, care should be taken not to dry or to allow the aqueousfluoropolymer dispersion to dry completely to the hydrophobic stateprior to applying the image over the coated dispersion. If the coateddispersion becomes hydrophobic, the image will not become fixed onto thesubstrate or may not even form or be transferred. Thus, prior to imageprinting or transfer, the hydrophobic material should be dried such thatan image can be applied through wetting of the ink.

[0039] The various processes of the invention may be carried out withany ink known in the graphic arts. Preferably, the inks used are basedaqueous inks, with the greatest benefit observed when dye based aqueousinks are employed. Thus, the invention is particularly well suited forus with commercial inkjet inks such as those available, for example,from Hewlett-Packard Corp. of Palo Alto, Calif., and LexmarkInternational of Lexington, Ky.

[0040] Mordants and dispersed hydrophobic materials used in practice ofthe invention may be applied to substrates in a wide variety of methodsknown for coating liquids on substrates. Examples include roll coating,gravure coating, spraying, inkjet printing, bar coating, knife coating,saturation coating methods, sponge coating, and the like.

[0041] Mordants and dispersed hydrophobic materials used in practice ofthe invention may be dried in a wide variety of methods depending onneed. Useful techniques include air drying under ambient conditions,drying in a forced air or convection oven, heat gun, infrared lamps,etc.

[0042] Images may be applied to substrates according to the variousprocesses of the invention by any means for imaging with liquid inksknown in the graphic arts. One preferred method for printing imagesaccording to the invention is an indirect transfer process in which theimage is printed as a reverse image on an image transfer medium, thentransferred to a second substrate by intimately contacting the imagetransfer medium with the second substrate and applying pressure (e.g.,with a hand-held roller, by hand, and the like), and then subsequentlyremoving the image transfer medium.

[0043] An “image transfer medium” is any medium which is capable ofreceiving an image and then transferring an image to another substrate.Useful image transfer media include sheets having a smooth imagingsurface and sheets having a micro-embossed imaging surface. Amicro-embossed surface has a topography wherein the averagemicro-embossed element pitch, that is, center to center distance betweenmicro-embossed elements is from about 1 to about 1000 micrometers andaverage peak to valley distances of individual micro-embossed elementsis from about 1 to about 100 micrometers. A “micro-embossed element”means a recognizable geometric shape that either protrudes or isdepressed.

[0044]FIG. 15 illustrates a preferred embodiment of an image transfermedium 10 that is constructed of a sheet 12 having an imaging surfacecharacterized by a micro-embossed image surface topography 14 ofmultiple wells or cavities 16 and peaks 18 and having a coating of anink release material 20. The imaging surface of the sheet is nonporous.“Nonporous” means that the integral imaging surface of the sheet is notsubstantially porous to liquid inks. “Ink release material” means amaterial that provides for the release of not only inks but otherprinted materials as well. The ink release material is used to lower thesurface energy of the micro-embossed image surface, which facilitatesink transfer. “Surface energy” as used herein is equal to the surfacetension of the highest surface tension liquid (real or imaginary) thatwill completely wet a solid with a contact angle of 0 degrees, which maybe determined by measuring the critical surface tension from staticcontact angles of pure liquids using the method of W. A. Zismandescribed in “Relation of Equilibrium Contact Angle to Liquid and SolidConstitution”, ACS Advances in Chemistry Series #43, American ChemicalSociety, 1961, pages 1-51, incorporated by reference herein. The imagetransfer medium 10 is useful for receiving an ink image and protectingthe ink image from abrasion, and then capable of transferring the ink toanother substrate. FIG. 15 also illustrates an ink drop 30 within onecavity 16 such that the outermost surfaces or peaks 18 of themicro-embossed topography, on a macroscopic level, control placement ofthe ink drop 30 before transfer.

[0045] Sheet 12 used in the image transfer medium can be made from anypolymer or combination of polymers capable of being micro-embossed inthe manner of the present invention.

[0046] The ink release coating is a coating that resides on themicro-embossed surface. The ink release coating may be continuous ordiscontinuous and is preferably continuous. The purpose or function ofthe ink release coating is to lower the surface energy of themicro-embossed surface of the image transfer medium, therebyfacilitating a more complete transfer of the ink to a second substrateto form an image of high color density to a second substrate. Withoutthe ink release coating, only portions of the image may transfer or onlya top portion of the ink contained in each cavity may transfer to thesecond substrate, requiring perhaps a second ink image printed andtransferred. Thus, useful ink release coatings are those coatings thatcan be applied or migrate to the micro-embossed surface of the sheet tolower the surface energy of the portions of the cavities which ink willcontact such that at least 20 percent, preferably at least 50 percent,even more preferably at least 75 percent of the ink is transferred asmeasured by reflectance color density.

[0047] Preferred ink release coatings include compositions comprisingsilicones, fluorochemicals, and polymers thereof. Alternatively,additives may be incorporated into polymeric materials used for sheetsor surfaces of sheets that migrate to the surface of the image transfermedium and provide a low surface energy coating, that is, ink releasecoating. These additives may be added to thermoplastic and/or thermosetresins that are extruded and micro-embossed to form image transfer mediaof the invention. Useful surface energy modifying additives includesilicone surfactants such as those available from OSi Specialties, Inc.,of Danbury, CN, under the tradename SLWET, and fluorinated surfactantssuch as those available under the tradename FLUORAD FC-1802, etc.,available from Minnesota Mining and Manufacturing Company, St. Paul,Minn.

[0048] Preferred ink release coatings provide the micro-embossed surfacewith a surface energy of about 43 dyne/centimeter or less, preferablyabout 30 dyne/centimeter or less, more preferably about 25dyne/centimeter or less. Ink release coating materials that will providesurface energies of 43, 30, and 25 dynes/centimeter or less arecommercially available.

[0049] In general, the choice of geometrical configuration of thespecific micro-embossed features does not greatly influence imagetransfer performance, so long as there is sufficient micro-embossedcapacity to control placement of an individual drop of ink. In somepreferred embodiments, the geometrical configuration is chosen such thatthe micro-embossed element pitch (i.e., center to center distancebetween micro-embossed elements) is less than about 340 micrometers. Infurther preferred embodiments, the micro-embossed micro-embossed elementdensity of the pattern is such that the cavity walls actually collapsewhen moderate pressure is applied by hand to effect the transfer of theimage.

[0050] For example, low density polyethylene walls micro-embossed as anorthogonal grid and having an average wall thickness of 10-25micrometers, spaced with a micro-embossed element pitch of 338micrometers, and having square cavities with a depth of 25 micrometers,completely collapse during image transfer with moderate hand pressure.On the other hand, the same low density polyethylene materialmicro-embossed with an orthogonal grid pattern with walls 10-25micrometers thick, spaced with a micro-embossed element pitch of 127micrometers, and having square cavities with a depth of 25 micrometersdo not collapse.

[0051] In general, the amount of ink transferred from films withcollapsible features is superior to those films containing more rigidfeatures. Silicone rubber micro-embossed elements are preferred, sincethey collapse under pressure, but quickly recover to their originalshape when pressure is removed so the film can be used again.

[0052] In a preferred embodiment, the micro-embossed imaging surfacetopology is chosen so that ink droplets printed onto the micro-embossedsurface do not protrude above the tops of the micro-embossed elementsthereby improving handling properties of imaged sheet.

[0053] In another image transfer medium, shown in FIG. 16, the imagetransfer medium 40 is constructed of a sheet 42 having an micro-embossedimaging surface topography 44 of multiple wells or cavities 46 and peaks48 wherein the micro-embossed or image surface has ink releaseproperties. In this embodiment, the micro-embossed imaging surfaceitself has ink release properties, that is, the micro-embossed surfacehas a surface energy that facilitates the transfer of ink from thesurface topography without any additional ink release coating added (SeeFIG. 15). The imaging surface of the sheet is also nonporous as definedabove.

[0054] Materials having a surface energy in the range of from about 43dyne/centimeter or less are suitable for use as sheets 42 or as amicro-embossed surface topography 44. Non-limiting examples of materialsthat provide a suitable surface energy include polymeric materials suchas polydimethylsiloxanes, fluorinated polymers, polyolefins (e.g., suchas polyethylene, polypropylene, etc.) and polyvinyl chloride. For usewith aqueous inks, useful materials have a surface energy of less thanabout 43 dyne/centimeter, with materials having a surface energy of fromabout 30 dyne/centimeter or less being preferred. For use withnon-aqueous inks (i.e., solvent based or 100 percent solids), materialshaving a surface energy of from about 30 dyne/centimeter or less areuseful, preferably from about 25 dyne/centimeter or less.

[0055] In another image transfer medium, shown in FIG. 17, the imagetransfer medium 50 is constructed of a sheet 52 having a micro-embossedimaging surface topography 54 of multiple posts 56. The posts may be anyprotruding geometric shape, for example, circular, oval, trapezoidal,spiral, square, triangular, octagonal, and the like. Preferably, thespace between posts is from about 10 to about 1000 micrometers, evenmore preferably from about 50 to about 800 micrometers and even morepreferably from about 200 to about 600 micrometers. Preferably, theheight of the posts ranges from about 5 to about 100 micrometers, morepreferably from about 10 to about 70 micrometers, even more preferablyfrom about 10 to about 40 micrometers. Preferably, the diameter of theposts ranges from about 10 to about 150 micrometers, more preferablyfrom about 10 to about 100 micrometers and even more preferably fromabout 30 to about 90 micrometers. Preferably, the density of the postsranges from about 1 to about 40 posts per square millimeter, morepreferably from about 2 to about 20 posts per square millimeter and evenmore preferably from about 2 to about 10 posts per square millimeter. Asshown above sheet 52 may be made from a material that provides an inkrelease property to the imaging surface. Alternatively, an ink releasecoating may be coated onto the imaging surface.

[0056] In another image transfer medium shown in FIG. 18, the imagetransfer medium 60 is constructed of a sheet 62 having a micro-embossedimaging surface topography 64 of wells or cavities 66 and posts 68. Thecavities are spaced such that they provide control over the placement ofthe ink droplets while the posts are spaced to prevent accidentalsmearing of the wet ink. Preferably, the pitch of the cavities is finerthan the pitch of the posts. However, the pitch of the cavities whencombined with the posts can typically be wider than the pitch ofcavities alone since the posts prevent the wet image from smearingduring handling. The posts may also be applied in a random manner to animaging substrate having cavities such that some of the posts are withina cavity. The height of the posts may or may not exceed the height ofthe walls of the cavities. As described above, the imaging surface maybe constructed of a material that provides an ink release property ofthe imaging surface may be coated with an ink release coating.

[0057] The sheets described in FIGS. 15-18 can be a solid film. Thesheets may be transparent or translucent, clear or tinted, or opticallytransmissive. The sheets 12 and 42 are preferably transparent.

[0058] Nonlimiting examples of polymeric films useful as sheets in theimage transfer media include thermoplastics such as polyolefins (forexample, polyethylene, polypropylene, polybutylene, copolymers ofstyrene and butadiene, copolymers of ethylene and propylene, etc.);poly(vinyl chloride); hydrolyzed or unhydrolyzed copolymers of ethylenewith vinyl acetate; polycarbonates; norbornene copolymers; fluorinatedthermoplastics such as copolymers and terpolymers comprisinghexafluoropropylene, vinylidene fluoride, tetrafluoroethylene, or vinylfluoride, and surface modified versions thereof, poly(ethyleneterephthalate) and copolymers thereof, polyurethanes, polyimides,acrylics, and filled versions of the above using fillers such assilicates, aluminates, feldspar, talc, calcium carbonate, titaniumdioxide, and the like. Also useful in the application are non-wovens,coextruded films, and laminated films made from the materials listedabove. A person of ordinary skill in the art can easily measure thesurface energy of any of the above films to determine whether the filmsprovide a suitable surface energy for use in an image transfer mediadescribed by FIG. 16 and the accompanying text.

[0059] More specifically, polyolefins can be ethylene homopolymers orcopolymers, such as “7C50” brand ethylene propylene copolymercommercially available from Union Carbide Co. of Houston, Tex. Otherspecifically useful films include “LEXAN” polycarbonate from GeneralElectric Plastics of Pittsfield, Mass., “ZEONEX” polymer from B. F.Goodrich of Richfield, Ohio, fluoropolymers such as “THV-500” and “THV250” polymers from Dyneon LLC of Oakdale, Minn., plasticized poly(vinylchloride), poly(ethylene terephthalate) copolymer “EASTAR” 6763 fromEastman Chemical Co. of Kingsport, Tenn., “AFFINITY” PL 1845 from DowChemical Co. of Midland, Mich., and SURLYN™ acrylic acid copolymers fromE. I. Du Pont de Nemours and Co. of Wilmington, Del.

[0060] In further embodiments of sheets shown in FIGS. 15-18, any sheetsuitable for feeding into an inkjet printer may be further coated,laminated, or co-extruded with one or more of the polymers suitable foruse in polymeric films of according to the invention and furthermicro-embossed (and, if necessary, coated with an ink release materialas described herein) to provide image transfer media of the invention.Non-limiting examples of such sheets are papers, including for examplexerographic grade papers, specialty inkjet papers, and coated papers,etc.; nonwoven materials, including for example spunbond polyolefins,etc.; card stock; envelopes; etc.

[0061] Thermoset materials are also additionally useful as materials forsheets or micro-embossed imaging surface topographies that have inkrelease properties without the use of an ink release coating. Forexample, reactive silicones (either two-part or moisture curable,UV-curable materials (e.g., acrylate mixtures) may be applied to amicro-embossed roll, cured and removed from the roll to give anmicro-embossed film having an inverse image of the roll.

[0062] The structure of the micro-embossed surface topography can be anystructure that provides cavities that will each hold at least 10 pL ofink. For example, the topographies for the cavities can range from theextreme of cubic cavities with parallel vertical, planar walls, to theextreme of hemispherical cavities, with any possible solid geometricalconfiguration of walls in between the two extremes. Specific examplesinclude conical cavities with angular, planar walls, truncated pyramidcavities with angular, planar walls, and cube corner shaped cavities.Other useful micro-embossed structures are described in PCT publicationsWO 00/73082 and WO 00/73083.

[0063] The pattern of the topography can be regular, random, or acombination of the two. “Regular” means that the embossing pattern isplanned and reproducible regardless of the pattern of the embossing.“Random” means one or more features of the micro-embossed elements areintentionally and/or systematically varied in a non-regular manner.Examples of features that are varied include for example, micro-embossedelement pitch, peak-to-valley distance, depth, height, wall angle, edgeradius, and the like. Combination patterns may for example comprisepatterns that are random over an area having a minimum radius of tencavity widths from any point, but these random patterns can bereproduced over larger distances within the overall pattern.

[0064] More than one drop of ink may be contained in a cavity becausethe mixing of the colors cyan, yellow, and magenta are required tocreate the infinite number of colors demanded in the inkjet industry.Thus, the volume of the cavities should be capable of holding as many asthree drops of different colors of ink. The volume of a cavity can rangefrom about 1 to about 20,000 pL, preferably from about 1 to about 10,000pL, more preferably from about 3 to about 1,000 pL, even more preferablyfrom about 30 to about 10,000 pL, and even more preferably from about300 to about 10,000 pL.

[0065] For applications in which desktop inkjet printers (typical dropsize of 3-20 pL) will be used to generate the image, cavity volumes offrom about 1000 to about 3000 pL are preferred. For applications inwhich large format desktop inkjet printers (typical drop size of 10-200pL) will be used to generate the image, cavity volumes of from about3,000 to about 10,000 pL are preferred.

[0066] Another way to characterize the structure of the cavities is todescribe the cavities in terms of aspect ratios. An “aspect ratio” isthe ratio of the depth to the width of the cavity. Useful aspect ratiosrange from about 0.01 to about 2, preferably from about 0.05 to about 1,and more preferably from about 0.05 to about 0.3.

[0067] The overall depth of the cavities depends on the shape, aspectratio, and desired volume of the cavities. For a cubic-shaped cavity,the depth ranges from about 5 to about 100 micrometers. For ahemispherical-shaped cavity, the depth ranges from about 7 to about 100micrometers. The depths of other geometrically shaped cavities reside inbetween these two extremes for a given volume.

[0068] Micro-embossed element pitch of the micro-embossed image transfermedia of the invention are in the range of from 1 to about 1000micrometers, preferably from 10 to about 500 micrometers, morepreferably from about 50 to about 400 micrometers. It is recognized thatin some embodiments of the invention, it may not be necessary, ordesirable, that uniform micro-embossed element pitch be observed betweenmicro-embossed elements, nor that all features be identical. Thus, anassortment of different types of features, for example, cavities orwells with, perhaps, an assortment of micro-embossed element pitches maycomprise the micro-embossed surface of the image transfer mediaaccording to the invention.

[0069] Image transfer media of the invention may be prepared and used inmany dimensions. Useful lengths may be from about 1 centimeter up to2,000 meters or even longer (especially when used in roll form). Usefulwidths may be from about 0.5 centimeter up to about 250 centimeters oreven wider. Useful thicknesses of image transfer media of the inventionmay range from about 25 micrometers up to 0.5 millimeter or even higherso long as the material may be printed by inkjet means.

[0070] The image transfer media of the invention may also optionallyhave an ink receptive coating on the micro-embossed imaging surface. Theink receptive coating may comprise one or more layers. The purpose ofthe ink receptive coating is to limit migration of colorant both priorto and after subsequent image transfer. The ink receptive coating may beused on any image transfer media described in this application.

[0071] Useful ink receptive coatings are hydrophilic and aqueous inksorptive. Such coatings include, but are not limited to, polyvinylpyrrolidone, homopolymers and copolymers and substituted derivativesthereof; vinyl acetate copolymers, for example, copolymers of vinylpyrrolidone and vinyl acetate, copolymers of vinyl acetate and acrylicacid, and the like, and hydrolyzed derivatives thereof; polyvinylalcohol, acrylic acid homopolymers and copolymers; co-polyesters such asthe VITEL co-polyesters available from Bostick, Middleton, Mass.;acrylamide homopolymers and copolymers; cellulosic polymers; styrenecopolymers with allyl alcohol, acrylic acid, and/or maleic acid oresters thereof; alkylene oxide polymers and copolymers; gelatins andmodified gelatins; polysaccharides, and the like, as disclosed in U.S.Pat. Nos. 5,766,398; 4,775,594; 5,126,195; and 5,198,306. Vinylpyrrolidone homopolymers and copolymers are preferred.

[0072] Optionally, the ink receptive coatings may also include additivesthat provide a visual property to the transferred image. Such additivesinclude glitter, glass bubbles, pigments, mica, UV absorbers andstabilizers, etc.

[0073] Additionally, the image transfer media of the invention may alsohave one or more surfactants coated onto the micro-embossed imagingsurface. Examples of useful surfactants include those described in U.S.Pat. No. 5,932,355 at column 7, lines 22-31, incorporated by referencein this application.

[0074] The transfer medium 10 optionally has an adhesive layer on themajor surface of the sheet opposite micro-embossed image surface 12 thatis also optionally but preferably protected by a release liner. Afterimaging, the receptor medium 10 can be adhered to a rigid substratebefore image transfer.

[0075] The choice of adhesive and release liner depends on usage desiredfor the image graphic.

[0076] Pressure-sensitive adhesives can be any conventionalpressure-sensitive adhesive that adheres to both the polymer sheet andto the surface of the item upon which the transfer medium having theprecise image is to be placed. Pressure-sensitive adhesives aregenerally described in Satas, Ed., Handbook of Pressure SensitiveAdhesives 2nd Ed. (Von Nostrand Reinhold 1989), the disclosure of whichis incorporated by reference. Pressure-sensitive adhesives arecommercially available from a number of sources. Particularly preferredare acrylate pressure-sensitive adhesives commercially available fromMinnesota Mining and Manufacturing Company, and generally described inU.S. Pat. Nos. 5,141,790; 4,605,592; 5,045,386; and 5,229,207; and EPOPatent Publication EP 0 570 515 B1.

[0077] Release liners are also well known and commercially availablefrom a number of sources. Nonlimiting examples of release liners includesilicone coated kraft paper, silicone coated polyethylene coated paper,silicone coated or non-coated polymeric materials such as polyethyleneor polypropylene, as well as the aforementioned base materials coatedwith polymeric release agents such as silicone urea, fluorinatedpolymers, urethanes, and long chain alkyl acrylates, such as defined inU.S. Pat. Nos. 3,957,724; 4,567,073; 4,313,988; 3,997,702; 4,614,667;5,202,190; and 5,290,615; the disclosures of which are incorporated byreference herein and those liners commercially available as POLYSLIKbrand liners from Rexam Release of Oakbrook, Ill., and EXHERE brandliners from P.H. Glatfelter Company of Spring Grove, Pa.

[0078] Method of Forming Micro-Embossed Image Surface

[0079] The micro-embossed imaging surface can be made from anycontacting technique such as casting, coating, or compressingtechniques. More particularly, micro-embossing can be achieved by atleast any of (1) casting a molten thermoplastic using a tool having apattern, (2) coating of a fluid onto a tool having a pattern,solidifying the fluid, and removing the resulting micro-embossed solid,or (3) passing a thermoplastic film through a nip roll to compressagainst a tool having that micro-embossed pattern. Desired embossingtopography can be formed in tools via any of a number of techniqueswell-known to those skilled in the art, selected depending in part uponthe tool material and features of the desired topography. Illustrativetechniques include etching (e.g., via chemical etching, mechanicaletching, or other ablative means such as laser ablation or reactive ionetching, etc.), photolithography, stereolithography, micromachining,knurling (e.g., cutting knurling or acid enhanced knurling), scoring orcutting, etc.

[0080] Alternative methods of forming the micro-embossed image surfaceinclude thermoplastic extrusion, curable fluid coating methods, andembossing thermoplastic layers which can also be cured.

[0081] Other specific examples of useful image transfer media includethose described in U.S. Pat. No. 6,153,038.

[0082] Depending on the specific formulation and use intended,additional materials may be incorporated into the mordants and/ordispersed hydrophobic materials employed in various aspects of theinvention, including adjuvants such as fillers (e.g., glass bubbles,silica, etc.), surfactants, emulsifiers (e.g., water soluble polymers),coating aids, biocides, UV stabilizers, antioxidants, fungicides,optical brighteners, co-solvents (e.g., alcohols, glycols, glycolethers, etc.), humectants, and the like.

[0083] Aspects and advantages of this invention are further illustratedby the following examples, but the particular materials and amountsthereof recited in these examples, as well as other conditions anddetails, should not be construed to unduly limit this invention.

EXAMPLES

[0084] The following materials and abbreviations are used in theexamples that follow:

[0085] “EPSON STYLUS COLOR” is a trade designation and model for aninkjet printer, available from U S Epson, Inc. of Torrance, Calif.

[0086] “HP51626” black and “C1823” series inkjet inks, “DESKJET PLUS”and “DESKJET 855Cse” thermal inkjet printers are available from theHewlett-Packard Company of San Diego, Calif.

[0087] The 100 percent cotton T-shirt cloth used in the examples wasHANES SPECIAL-TEE brand, 100 percent combed cotton (white), availablefrom Hanes Companies of Winston Salem, N.C., and had a thickness of0.203 millimeters and basis weight of 104 μm².

[0088] Mayer Rods (i.e., wire-wound rods) are available from R DSpecialties, Inc. of Webster, N.Y. # 6 Mayer Rods give coatings ofnominal wet film thickness of 0.014 millimeter.

[0089] “FLUORAD FC-359” (an aqueous dispersion of a fluoroalkyl polymer(approximately 20 percent)), “FLUORAD FC-461” (a aqueous dispersion of afluoroalkyl copolymer (approximately 27 percent), “FLUORAD FC-1355” (anaqueous dispersion of a fluoroalkyl polymer (approximately 15 percent)),and “FLUORAD FC-280” (an aqueous dispersion of a fluoroalkyl polymer(approximately 30 percent)) are trade designations for aqueousfluoropolymer dispersions available from Minnesota Mining andManufacturing Company of St. Paul, Minn.

[0090] “3M FINE GRADE SANDING SPONGE” was obtained from Minnesota Miningand Manufacturing Company.

[0091] “ASPEN SELECT GRADE HOBBY WOOD” is a trade designation for aspenwood, which has been sanded smooth for use by hobbyists. It orequivalents may be obtained at hobby and craft stores.

[0092] Alumina-HPMC is an aqueous solution (2.5 percent solids) of analuminum ion-crosslinked hydroxypropyl methylcellulose polymer networkimpregnated with a colloidal aluminum oxide-hydroxide sol as describedin U.S. Pat. No. 5,686,602 using the procedure of Example 1 and the acidof Example 2, incorporated by reference in this application.

[0093] “DISPAL 23N4-20” is a 25 weight percent solids aqueous aluminadispersion, available from Vista Chemical Co. of Houston, Tex.

[0094] “ERA” is a brand name for laundry detergent, available fromProcter and Gamble Co. of Cincinnati. Ohio.

[0095] “FREESOFT 970” is a trade designation for a silicone emulsion (20weight percent solids in water), available from B.F. Goodrich Co. ofAkron, Ohio.

[0096] “AIRFLEX 465” is an aqueous dispersion of ethylene-vinyl acetatecopolymer (approximately 60 weight percent solids), available from AirProducts and Chemicals, Inc. of Allentown, Pa.

[0097] “NALCO 2326” (a colloidal silica sol, 5 nanometer particle size),“NALCO 2327”, (a colloidal silica sol, 20 nanometer particle size),“NALCO 2329”, (a colloidal silica sol, 75 nanometer particle size), and“NALCO 1056” (alumina-coated silica, 20 nanometer particle size), areavailable from Nalco Chemical Co. of Naperville, Ill.

[0098] “AEROSIL A130” is a trade designation for dry fumed silica,available from DeGussa Corp. of Ridgefield Park, N.J.

[0099] “3M SCOTCHCAL GRAPHIC MARKING FILM” (a trade designation 0.05millimeter thickness, white polyvinyl chloride film), and “SCOTCH BRANDMAGIC TAPE” (a trade designation for transparent tape) are bothavailable from Minnesota Mining and Manufacturing Company.

[0100] Silicone coated LDPE/PET/HDPE (i.e., low densitypolyethylene/polyethylene terephthalate/high density polyethylene) filmsurface and polyethylene coated paper each having a thin siliconetopcoat on the LDPE surface, are available from Rexam Release.

[0101] Aluminum nitrate, aluminum sulfate, and3-aminopropyltrimethoxysilane are available from general chemicalvendors such as from Aldrich Chemical Co. of Milwaukee, Wis.

[0102] Micro-Embossed Image Transfer Media

[0103] The following microstructured patterns were used in some of theexamples, which follow and are referred to as Pattern 1 and Pattern 2.Both patterns were micro-embossed by calendering of a continuous web ofthe materials to be micro-embossed using a corresponding engraved rollhaving an inverse image as the roll contacting the micro-embossed sideof the web, unless otherwise specified.

[0104] Pattern 1 is a “75 LPI” pattern referred to in the examples is anarray of square cavities that are 25 micrometers deep and having amicro-embossed element pitch of 332 micrometers and walls that are 9micrometers thick at their top and 22 micrometers thick at their base.

[0105] Pattern 2 is a “130 LPI” pattern of square cavities of 197micrometers micro-embossed element pitch, cavity depth of 15micrometers, and included wall angle of 60°. The wall thickness is 20micrometers at the bottom of the cavity. Additionally, at the center ofthe bottom of this cavity resides a second cavity that increases thetotal volume of the structure. This second cavity is pyramid shaped(four sides proceeding to a point at the deepest point of the two-cavitystructure). It is 38 micrometers wide at the opening, and is 10micrometers deep with a 125° included angle of descent.

[0106] General Procedure a for Preparing Imaged Articles:

[0107] A digitally created image stored on a computer was imaged with anEPSON STYLUS color inkjet printer operating at the 720 dpi, Coated720×720 Media settings onto piece of 0.1 millimeter polyvinylidenedichloride primed polyethylene terephthalate film coated with afluorinated release layer (image transfer medium) prepared as describedin Comparative Example 1 of U.S. Pat. No. 5,760,126, incorporated byreference herein. This image, while still wet, was transferred onto 100percent cotton cloth that had been dampened with an aqueous liquid (wetadd on of approximately 10 weight percent) by intimately contacting theimaged surface of the image transfer medium with a printable surface ofa desired substrate, applying firm hand pressure to the back side of theimage transfer medium, and removing the image transfer medium. Theresulting wet image was placed in an air convection oven for 5 minutesat 100° C.

Comparative Example 1

[0108] This comparative example illustrates the problems associated withimaging cotton cloth using inkjet printer inks.

[0109] A 15 centimeter by 15 centimeter piece of cotton cloth was imagedaccording to General Procedure A using deionized water to dampen thecotton cloth. The imaged cloth was placed into a capped vial of water(30 grams of water). The vial was agitated for a minute to wet thecloth, then left to stand at ambient room temperature for about 24hours. The water extract showed significant color, due to the dyesleaching out into the solution. A UV-Vis absorption spectrum was takenof the resulting solution, showing several absorption bands, due to thevarious colors coming out into the solution. The maximum absorption wasfor the magenta color, which has a visible absorption maximum at 560nanometers. The optical density (i.e., absorbance) of the solution at560 nanometers was 1.18. Image quality (i.e., color density andresolution) was badly degraded.

Comparative Example 2

[0110] Alumina-HPMC was applied to a cotton cloth with a #6 Mayer Rodand was imaged according to General Procedure A. The imaged cloth wasplaced into a capped vial of water (30 grams). The vial was agitated fora minute to wet the cloth, then left to stand at ambient roomtemperature for about 24 hours. The water extract showed less color dueto the dyes leaching out into the solution than seen in ComparativeExample 1.

[0111] The optical density of the solution at 560 nanometers was 0.40.The image quality was much better than was that of Comparative Example 1before and after soaking in water.

Comparative Example 3

[0112] A water-based dispersion of fluoropolymer, FLUORAD FC-359, wasapplied to a cotton cloth with a # 6 Mayer Rod. An image was applied andthe resulting image dried according to General Procedure A.

[0113] The imaged cloth was placed into a capped vial of water (30 gramswater). The vial was agitated for a minute to wet the cloth, then leftto stand at ambient room temperature for about 24 hours. The waterextract showed less color due to the dyes leaching out into the solutionthan seen in Comparative Example 1.

[0114] The optical density of the solution at 560 nanometers was 0.68.The overall image was better quality than that of Comparative Example 1,but poorer than the image of Comparative Example 2 after soaking inwater.

Comparative Example 4

[0115] A 10 percent solution of aluminum nitrate in water was applied tocotton cloth (T-shirt) with a #6 Mayer Rod. This cloth was imaged byGeneral Procedure A. The dried imaged cloth was placed into a vial ofwater. After some agitation, immediately the solution became colored.The optical density of the solution was greater than 2, with very littleimage apparent on the cloth.

[0116] A repeat of this procedure using aluminum sulfate in place ofaluminum nitrate gave the same result.

Example 1

[0117] This is an illustrative example of an image fixing treatmentaccording to the invention.

[0118] A solution was made of the following ingredients: alumina-HPMCsolution 5 parts by weight FLUORAD FC-359 1 part by weight

[0119] The resulting 3 percent (by solids) aqueous solution was mixedwell and applied to cotton cloth with a # 6 Mayer Rod. A piece of cottoncloth was coated with the above composition using a # 6 Mayer Rod andwas imaged according to General Procedure A. The imaged cloth was placedinto a capped vial of water (30 grams of water). The vial was agitatedfor a minute to wet the cloth, then left to stand at ambient roomtemperature for about 24 hours. The water extract showed much less colordue to the dyes leaching out into the solution than seen in ComparativeExample 1.

[0120] The optical density of the solution at 560 nanometers was 0.23.The image quality was better than that of the image of ComparativeExamples 2 and 3 after soaking in water.

Example 2

[0121] These are illustrative examples of image fixing treatmentsaccording to the invention.

[0122] A number of examples were performed using the same twoingredients as in Example 1 in differing ratios. Examples were carriedout as previously described in Example 1, and the images tested forcolorfastness as before, except that the coatings were sprayed with aaerosol dispenser (wet add on weight was in the range of 100-140 gramsper square meter). TABLE 1 Alumina- FLUORAD Absorbance at HPMC FC-359560 Nanometers (Weight (Weight of Water Example No. Percent) Percent)Solution 2a 95 5 0.34 2b 90 10 0.32 2c 83.3 16.7 0.23 2d 75 25 0.12 2e50 50 0.06 2f 30 70 0.38

Examples 3a-3d

[0123] These are illustrative examples of an image fixing treatmentaccording to the invention.

[0124] Weight ratios of 5 parts of alumina-HPMC to 1 part of thefluoropolymer were used. The procedure of Example 2 was repeated usingthe materials and amounts described in Table 2, and the images testedfor colorfastness as before. Results are presented in Table 2. TABLE 2Alumina- HPMC Fluorinated Absorbance at 560 (Weight Additive Nanometersof Water Example No. Percent) (Weight Percent) Solution Comparative 0 01.18 Example 1 3a 83.3 FLUORAD FC- 0.23 359, 16.7 3b 83.3 FLUORAD FC-0.12 461, 16.7 3c 83.3 FLUORAD FC- 0.50 1355, 16.7 3d 83.3 FLUORAD FC-0.26 280, 16.7

Example 4

[0125] These are additional illustrative examples of image fixingtreatments according to the invention.

[0126] Instead of alumina-HPMC, DISPAL 23N4-20 (a commercially availableaqueous alumina dispersion) was used. This was mixed with fluoropolymer,then coated with a # 6 Mayer Rod onto the cloth to dampen the cloth. Thecomposition contained a ratio of 4.7 parts DIS PAL 23N4-20 to 1 part ofFLUORAD FC-461. An image was applied and the resulting image dried as inGeneral Procedure A. The water soak test of Example 3 was carried out onthese samples, with the exception that a 0.1 percent commercial laundrydetergent (ERA brand) in water solution was used to test the imagedfabric. The result obtained with this test was an optical density at 560nanometers of 0.013. Other ratios varying from 10:1 down to 2:1 byweight of DISPAL 23N4-20: FLUORAD FC-461, also gave good image qualityafter soaking in water for 24 hours.

Example 5

[0127] This is an illustrative example of an image fixing treatmentaccording to the invention.

[0128] A solution was made with AIRFLEX 465 latex polymer and DISPAL23N4-20 (each component is 50 percent by weight in the final solution,which is 30 percent solids in water). A cotton cloth was coated withthis solution using a #6 Mayer Rod, then subsequently imaged as inComparative Example 1 while still damp. Detergent resistance wasmeasured as in Example 4. The optical density of the colorant insolution at 560 nanometers was 0.15.

[0129] A solution was made containing 3 parts alumina-HPMC to 4 parts ofthe AIRFLEX 465 (solution is 16 percent by weight). A cotton cloth wascoated with this solution using a #6 Mayer Rod, then subsequently imagedas in Comparative Example 1 while still damp. Detergent resistance wasmeasured as in Example 4. The optical density of the colorant insolution at 560 nanometers was 0.21.

Example 6

[0130] This example demonstrates the utility of using FLUORAD FC-359 asan aqueous inkjet ink receptive coating for a nonporous polyvinylchloride film with subsequent heating to provide a water repellentfinished print.

[0131] A piece of 3M SCOTCHCAL GRAPHIC MARKING FILM was coated withFLUORAD FC-359 at ambient temperature using a #16 Mayer Rod. The coatingwas subsequently dried at ambient temperature for two hours. Afterdrying, the coated film was printed upon with black ink (HP51626 blackinkjet ink), using a DESKJET PLUS inkjet printer operating in standardmode. The test pattern consisted of black text.

[0132] After printing, the ink was observed to feel dry to the touch ina few minutes. At this time, the printed substrate was placed in an ovenat 100° C. for two minutes. After heating, the substrate was found to berepellent to aqueous and oily fluids. Using the protocol described inthe American Association of Textile Chemists and Colorists (AATCC)Standard Test Method No. 118-1983, which is a test based on theresistance of a fabric to penetration by oils of varying surfacetensions, a static oil repellency rating of 7 (i.e., excellent) wasobtained. Oils and their associated rating numbers are shown in Table 3below. TABLE 3 AATCC Oil Repellency Rating Number Oil 1 mineral oil C85:15 mineral oil:n-hexadecane 2 65:35 mineral oil:n-hexadecane 3n-hexadecane 4 n-tetradecane 5 n-dodecane 6 n-decane 7 n-octane 8n-heptane

[0133] Using the same static repellency test, but substituting water,isopropanol, and mixtures thereof, aqueous repellency ratings weredetermined as shown in Table 4. After soaking in water minutes, partialrelease of the ink was observed. The source of the weakening of thecoating appeared to be at the edges, where encroachment of water couldbe seen after several minutes. TABLE 4 Aqueous Repellency Rating NumberLiquid 0 water 1 90 parts water/10 parts isopropanol (wt/wt) 2 80 partswater/20 parts isopropanol (wt/wt) 3 70 parts water/30 parts isopropanol(wt/wt) 4 60 parts water/40 parts isopropanol (wt/wt) 5 50 partswater/50 parts isopropanol (wt/wt) 6 40 parts water/60 parts isopropanol(wt/wt) 7 30 parts water/70 parts isopropanol (wt/wt) 8 20 partswater/80 parts isopropanol (wt/wt) 9 10 parts water/90 parts isopropanol(wt/wt) 10 isopropanol

[0134] When transparent tape (SCOTCH BRAND MAGIC TAPE) was manuallyapplied with pressure against the printed side of the substrate, noadhesion was observed. Also, the coating appeared to adhere well to thesubstrate as fingernail scratching did not remove the coating of theprinted characters.

[0135] Preparations of Compositions 1a-1e

[0136] This example shows the improvement in image fixing abilityachieved by blending cationically functionalized inorganic particulateswith fluorocarbon materials.

[0137] NALCO 2327, and NALCO 2329 colloidal silica sols wereamine-functionalized on their surface by reaction with3-aminopropyltrimethoxysilane as follows:

[0138] Each collidal silica sol was diluted as necessary to achieve 5-10percent solids by weight and the pH was reduced to 3.5-4 by addition ofa suitable amount of concentrated acetic or sulfuric acid. An amount of3-aminopropyltrimethoxysilane (hereinafter denoted as APTMS) was addedto a separate aliquot of water; and the pH was adjusted to match that ofthe dispersion before its addition to the dispersion with good mixing;the mixture was then stirred and heated to 50° C.-90° C. for 16 hours.The amount of APTMS added, which is shown in the Table 5, was based onthe theoretical surface area of the colloid. TABLE 5 APTMS(millimoles/gram Composition Silica SiO₂) 1a (comparative) NALCO 1056 0(diluted to 5-10 percent solids at pH = 4 1b NALCO 2326 1.5 1c NALCO2327 0.9 1d NALCO 2329 0.35

[0139] Fumed silica (AEROSIL A130) was also reacted with APTMS in thefollowing manner:

[0140] AEROSIL A130 was dispersed in toluene at 3 percent solids, and atheoretical excess of APTMS (1.4 gram APTMS per gram SiO₂) added to thedispersion. The mixture was refluxed for 16 hours. The silica wasfiltered away from the solvent and washed two times with methanol,followed by refluxing in methanol for at least 24 hours before a finalfiltration and drying of the solids in vacuo. Coating samples were madefrom this material by simple dispersion of the silica in water at pH ofabout 4 (referred to hereinafter as Composition 1e).

[0141] Samples for printing, printing operations, and analysis of theprints were generated as described in Example 6 above. In each case, anadmixture of the coating components in water was blended immediatelybefore coating.

[0142] Compositions 1a and 1c-1e were blended, respectively, withFLUORAD FC-359 in ratios shown in the table below. Each of theseadmixtures was coated onto the PVC substrate as used in Example 6, witha #16 Mayer Rod. Drying was accomplished over 2 hours at ambienttemperature, at which the film was printed and heated in an oven at 100°C. for two minutes. Imaging behavior, appearance and repellency of thesubstrate after printing and heating is compared in Table 6. TABLE 6AATCC Oil Aqueous Appearance Repellency Repellency Inorganic Blend Ratioof Printed Image After Rating Rating Component Inorganic:FC-359Properties Heating Number Number Composition 1:1 Dry in 2-3 min. Glossy,7 10 1b Good image smooth resolution Composition 1:1 Dry in 2-3 min.Glossy, 7 10 1c Good image smooth, resolution slight yellowingComposition 1:1 Ink beaded up; Glossy, not  0 1a poor drying, smooth,measured poor image slight quality yellowing Composition 5:1 Better inkGlossy, not  0 1a wetting but ink smooth measured bled, dry time waspoor Composition 2:1 Dry in 2-3 min. Glossy, 7 10 1d Good image smoothresolution Composition 1:1 Good drying, Chalky, not  0 1e resolution;ink matte measured was faded in appearance appearance

[0143] The following examples show the effectiveness of fixing agents ofthe invention when used with inkjet printing onto cotton fabric.

Example 7

[0144] A blend of 95 parts DISPAL 23N4-20 and 5 parts FREESOFT 970 wasprepared and adjusted with deionized water to 20 weight percent solids.A sample of cotton material (T-shirt type) was sprayed with this blend(100 weight percent wet add on). The treated fabric was imaged byGeneral Procedure A, except that the drying was done at 65° C. for 15minutes, and the printer used was an DESKJET 855Cse (presentationquality/glossy paper settings) thermal inkjet printer. The image wasallowed to dry at ambient room temperature for 24 hours before amicrograph was taken. Results are shown as magnified digital imagesdesignated FIGS. 1 and 2.

Comparative Example 5

[0145] Comparative Example 5 was a sample of cotton material (T-shirttype) sprayed with water (100 weight percent wet add on) and imagedaccording to Example 7. The image was allowed to dry at ambient roomtemperature for 24 hours before a micrograph was taken. Results areshown as magnified digital images designated FIGS. 3 and 4.

Examples 8a-8f

[0146] Blends of the DISPAL 23N4-20 sol were made with FREESOFT 970 andadjusted to 20 weight percent solids with deionized water, then sprayedonto cotton T-shirt cloth. The treated fabric was imaged as in Example7.

[0147] The imaged cloths were immersed in a 0.1 percent ERA detergentsolution for 24 hours. Optical density at 565 nanometers of thedetergent solution (a measure of dye wash out) was measured. TABLE 7DISPAL 23N4-20/ Wet add on FREESOFT 970 (Weight Absorbance at ExampleNo. (Weight/Weight) Percent) 565 Nanometers 8a 95:5  100 0.19 8b 90:10100 0.12 8c 90:10 50 0.46 8d 90:10 200 0.06 8e 80:20 100 0.17 8f 60:40100 0.1

[0148] Example 8b was repeated, with the imaged cloth allowed to dry atambient room temperature (22° C.) for 24 hours, rather than the abovedrying conditions. The same soak test gave a final result of 0.05 as theoptical density at 565 nanometers.

Examples 9a and 9b

[0149] This example demonstrates utility of the invention for printingwooden substrates. ASPEN SELECT GRADE HOBBY WOOD was sanded with a 3MFINE GRADE SANDING SPONGE before addition of fixing agent. The fixingagent used was a combination of 95 weight percent DISPAL 23N4-20 and 5weight percent FREESOFT 970 and diluted with water. The aqueous mixture(20 percent total solids) was sprayed onto one side of the wood to givean average wet coating weight of 50 g/m².

[0150] A test pattern consisting of adjacent colored blocks of cyan,magenta, yellow, black, red, green, and blue along with narrow lines ofthese colors crossing color bars were printed onto a polyethylene coatedpaper having silicone topcoat using a Hewlett-Packard DESKJET 855Csethermal inkjet printer in presentation quality/glossy paper mode. Theinked side of the image transfer medium was subsequently placed inintimate contact with the treated aspen prepared above, and sufficientpressure applied to cause transfer of the image to the wood (Example 9a)as shown in magnified digital image designated FIG. 5.

[0151] A second transfer was carried out in the same manner except thatthe image transfer medium further comprised a micro-embossed topography(Pattern 1) on the surface of the polyethylene coated paper having asilicone topcoat as shown in magnified digital image designated FIG. 6.

[0152] The resulting transferred images clearly showed differences inresolution attributable to the presence or absence of micro-embossedtopography used to affect the transfer of ink to the wood surface. Ascan be seen in magnified digital images, FIGS. 5 and 6, the transferredimage from the smooth film is prone to show where the ink beaded up, rantogether in an uncontrolled fashion, and/or smeared before or duringtransfer. By comparison, the image transferred by the film having amicro-embossed topography has good resolution and ink placement.

[0153] Machine Wash Test Procedure

[0154] Imaged cloth samples were combined with 1.9 kg of cotton fabricsheets and placed into a SEARS AUTOMATIC WASHER (1996 Model obtainedfrom Sears & Roebuck Co. of Chicago, Ill.). WISK ULTRA detergent (35grams available from Unilever United States, Inc. of New York, N.Y.) wasadded to the combined load and the normal wash mode cycle was initiated(41+/−2° C., 12 minute cycle).

[0155] The washed samples were dried together with the ballast load in aSEARS TUMBLE CLOTHES DRYER (1996 Model year, obtained from Sears &Roebuck Co.) using the medium heat cycle setting (65+/−5° C. for aduration of 45 minutes.

Comparative Examples 6-8 and Example 10

[0156] These examples demonstrate the advantage of using image fixingagents according to the present invention.

[0157] Cotton T-shirt cloth (Hanes Special-Tee brand) was cut into testpatches of approximately 22 centimeters by 14 centimeters and sprayedwith aqueous treatments at 100 percent wet add on by weight (i.e., thewet article weight was twice that of the original dry weight).

[0158] The coated cotton test patches of Comparative Examples 6-8 andExample 10 below were imaged as follows: a polyethylene coated paperhaving a silicone topcoat micro-embossed with Pattern 1 was printedusing an DESKJET 855Cse thermal ink-jet printer (presentation quality/HPglossy paper settings) with a test pattern containing both solid blocksof color and lines of color through color bars. The inked sheet wasimmediately applied to the damp fabric with moderate hand pressure forabout 1 minute, such that the ink transferred to the fabric. Each fabricsample was placed in a 65° C. oven for 15 minutes, then allowed to standovernight before taking measurements of reflectance optical densities.FIGS. 7-10 are magnified digital images corresponding to heat treatedunwashed cloths from Comparative Examples 6-8 and Example 10,respectively.

[0159] The samples were then washed according to the Machine Wash TestProcedure. FIGS. 11-14 are magnified digital images corresponding towashed and dried cloths from Comparative Examples 6-8 and Example 10,respectively. The areas of the cloths shown in FIGS. 11-14 correspond tothe same regions shown in FIGS. 7-10, respectively.

Comparative Example 6

[0160] Water was sprayed onto a cotton test patch at 100 percent wet addon by weight. FIG. 7 shows a magnified digital image of the resultantimage after image transfer. FIG. 11 shows a magnified digital image ofthe cloth after machine wash. Reflectance optical density measurementsfor the imaged samples prior to the Machine Wash Test Procedure andafter the Machine Wash Test Procedure were: Black Magenta Cyan YellowBefore machine wash test 0.99 1.16 1.11 0.86 After machine wash test0.57 0.80 0.67 0.02

Comparative Example 7

[0161] A solution of DISPAL 23N4-20 alumina sol (20 percent solids inwater) was sprayed onto a cotton test patch at 100 percent wet add on byweight. FIG. 8 shows a magnified digital image of the resultant imageafter image transfer. FIG. 12 shows a magnified digital image of thecloth after machine wash. Reflectance optical density measurements forthe imaged samples prior to the Machine Wash Test Procedure and afterthe Machine Wash Test Procedure were: Black Magenta Cyan Yellow Beforemachine wash test 0.68 1.19 1.19 0.91 After machine wash test 0.49 0.480.65 0.05

Comparative Example 8

[0162] FREESOFT 970 silicone emulsion (20 percent solids in water) wassprayed onto a cotton test patch at 100 percent wet add on by weight.FIG. 9 shows a magnified digital image of the resultant image afterimage transfer. FIG. 13 shows a magnified digital image of the clothafter machine wash. Reflectance optical density measurements for theimaged samples prior to the Machine Wash Test Procedure and after theMachine Wash Test Procedure were: Black Magenta Cyan Yellow Beforemachine wash test 0.94 1.25 1.23 1.12 After machine wash test 0.86 0.810.75 0.17

Example 10

[0163] A composition of 80 percent by weight of a solution of DISPAL23N4-20 alumina sol (20 percent solids in water) and 20 percent byweight FREESOFT 970 silicone emulsion (20 percent solids in water) wassprayed onto a cotton test patch at 100 percent wet add on by weight.FIG. 10 shows the resultant magnified digital image after imagetransfer. FIG. 14 shows a magnified digital image of the cloth aftermachine wash. Reflectance optical density measurements for the imagedsamples prior to the Machine Wash Test Procedure and after the MachineWash Test Procedure were: Black Magenta Cyan Yellow Before machine washtest 0.78 1.26 1.16 1.01 After machine wash test 0.56 0.55 0.71 0.20

Example 11

[0164] A piece of ASPEN SELECT GRADE HOBBY WOOD was prepared asdescribed in Example 9. A 25 weight percent solids dispersion of DISPAL23N4-20 was sprayed onto a surface of the wood with a wet coating weightof 51 g/m². The coated wood was then dried at a temperature of 80° C.for 2 minutes. An image was printed onto a Pattern 2 micro-embossedsilicone coated LDPE/PET/HDPE film using a DESKJET 855Cse (presentationquality/HP glossy paper settings) thermal inkjet printer. The image wastransferred to this article as described in Example 10. The resultingimaged article was placed in an 80° C. oven for 2 minutes. A 21 weightpercent solids dispersion of FREESOFT 970 was sprayed over the image ata coating weight of 60 g/m². The article was then dried for 10 minutesat 80° C.

[0165] The resulting image was bright and showed good resolution.Application of water from a deionized water bottle did not wash theimage off. Soaking the image in water for 72 hours resulted in aminorloss of color density.

What is claimed is:
 1. A method of providing a durable image on asubstrate comprising the steps of: coating a surface of the substratewith an aqueous mordant dispersion; printing or transferring a selectedimage onto the coated surface; optionally drying the image; applying adispersed hydrophobic material onto the image; and drying the dispersedhydrophobic material.
 2. The method of claim 1 further comprising thestep of heating the substrate above ambient temperature after the stepof drying the dispersed hydrophobic material.
 3. The method of claim 1wherein the aqueous mordant dispersion is selected from aqueousdispersions of mordants selected from the group consisting of polymericdye mordants, inorganic metal containing colloids, polymer bound metalion containing colloids, and combinations thereof.
 4. The method ofclaim 1 wherein the selected image is transferred onto the coatedsurface.
 5. The method of claim 4 wherein the image is transferred usinga micro-embossed image transfer medium.
 6. The method of claim 1 whereinthe dispersed hydrophobic material is selected from dispersions ofhydrophobic materials selected from the group consisting offluoropolymers, silicones, polyvinyls, polyesters, polyurethanes, andcombinations thereof.
 7. The method of claim 1 wherein the aqueousmordant dispersion is dried prior to printing or transferring the image.8. The method of claim 7 wherein the aqueous mordant dispersion is driedat a temperature of 100° C. or less.
 9. The method of claim 7 whereinthe aqueous mordant dispersion is dried at ambient temperature.
 10. Themethod of claim 1 wherein the dispersed hydrophobic material is dried ata temperature of 100° C. or less.
 11. The method of claim 1 wherein thedispersed hydrophobic material is dried at ambient temperature.
 12. Themethod of claim 1 wherein the image is dried at a temperature of 100° C.or less.
 13. The method of claim 2 wherein the substrate is heated untilthe dried hydrophobic material becomes hydrophobic.
 14. A method ofproviding a durable image on a substrate comprising the steps of:coating a surface of the substrate with a mixture comprising an aqueousdispersion of a mordant and a dispersed hydrophobic material; printingor transferring an image onto the coated substrate; and drying the imageand the coated mixture of dispersed mordant and hydrophobic material.15. The method of claim 14 further comprising the step of heating thesubstrate above ambient temperature.
 16. The method of claim 14 whereinthe image is transferred using an image transfer medium.
 17. The methodof claim 16 wherein the image transfer medium is a micro-embossed imagetransfer medium.
 18. The method of claim 14 wherein the image and saidcoated mixture is dried at a temperature of 100° C. or less.
 19. Themethod of claim 14 wherein the image and said coated mixture is dried atambient temperature.
 20. The method of claim 14 wherein the aqueousmordant dispersion is selected from aqueous dispersions of mordantsselected from the group consisting of polymeric dye mordants, inorganicmetal containing colloids, polymer bound metal ion containing colloids,and combinations thereof.
 21. The method of claim 14 wherein thedispersed hydrophobic material is selected from dispersions ofhydrophobic materials selected from the group consisting offluoropolymers, silicones, polyvinyls, polyesters, polyurethanes, andcombinations thereof.